I have the latest version (Build 3).

When exiting, I'm regularly left with a gray box in my lower left, blocking my Desktop. It only shows "Help" in the top left and, indeed, one can access Realband's "Help" from it. I can't make it go away. Going to Task Manager it indicates there are no programs running.

I have to reboot, to be able to get rid of it and have access to my Desktop again.